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From: Cecil Westerhof <Cecil@decebal.nl>
Newsgroups: comp.lang.java.programmer
Subject: Re: Working with an array of TreeSet
Date: Wed, 11 May 2016 09:05:16 +0200
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On Wednesday 11 May 2016 02:14 CEST, Eric Sosman wrote:

> On 5/10/2016 5:22 PM, Cecil Westerhof wrote:
>> On Tuesday 10 May 2016 18:19 CEST, Marcel Mueller wrote:
>> [...]
>>> The more interesting question is why you need an array of TreeSet.
>>> What is the semantic meaning of from? And what is the meaning of
>>> to?
>>
>> I am mapping the connections of paths between nodes in a graph.
>> From a node to a node.
>
> Perhaps a
>
> 	Map<Node,Set<Node>>

All values from 1 to maxNode are there, but with Map I do not need a
dummy with a null. So this is better I think, yes. Also when I get a
situation where not every node number exists, this is certainly
better. Thanks.


> or (if there can be more than one Edge from Node X to Node Y)
>
> 	Map<Node,Collection<Node>>

There is only one. That is why I used TreeSet.

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof